It is desirable to know the temperature of all the elements of an electronic system as well as to know the rates of change of temperature and the ultimate temperature that the elements would achieve if present power conditions continued. For example, consider a circuit board that includes a CPU, RAM and a hard disk drive. Each of these elements generates heat while in operation and that heat affects each of them individually. Heat radiated or conducted from each can affect the other components. It would be desirable to determine electronically the amount of heat generated by each of the components to permit proactive action if undesirable conditions appear to be likely to occur.